STRUCTURAL-ANALYSIS OF ALEKSINAC OIL-SHALE KEROGEN BY HIGH-RESOLUTION SOLID-STATE C-13 NMR-SPECTROSCOPY

A sample of kerogen from Aleksinac oil shale was examined by high-resolution solid-state C-13 n.m.r. spectroscopy. The presence and relative proportions of kerogen structural units were estimated using a combination of NQS and T-1 rho C methods with a peak-synthesis technique applied to the C-13 CP-MAS spectrum. Relaxation parameters from these experiments were used to estimate differences in relative 'mobility' of various structural units. The kerogen was found to be highly aliphatic and to contain similar to 79% long-chain aliphatic plus alicyclic structures, as well as similar to 9% aromatic structures. These findings are in good agreement with the characterization of the same kerogen from its oxidation products.